This invention relates to circuitry for converting logical signals from the levels typically used for transistor-transistor logic ("TTL") to the levels typically used for complementary metal oxide semiconductor ("CMOS") logic.
It is highly desirable for circuits of the type described above to draw little or no power for any valid TTL input signal level. Such circuits should also have high input impedance so that little or no current flows between the circuit and the TTL input signal source at any input signal level.
In view of the foregoing, it is an object of this invention to provide TTL-to-CMOS converters or buffers which draw little or no power for any valid TTL input signal level.
It is another object of this invention to provide TTL-to-CMOS converters or buffers which have very high input impedance at all input signal levels.